The assassination of Rajiv Gandhi, the former Prime Minister of India, occurred on May 21, 1991, in Sriperumbudur, Tamil Nadu, during an election campaign event. The assassination was carried out by Kalaivani Rajaratnam, also known as Thenmozhi Rajaratnam or Dhanu, a 22-year-old member of the Liberation Tigers of Tamil Eelam (LTTE), a Sri Lankan Tamil separatist rebel organization. At the time of the assassination, India had recently concluded its involvement through the Indian Peace Keeping Force in the Sri Lankan Civil War.

Rajiv Gandhi was actively campaigning in the southern states of India with G.K. Moopanar. After a campaign stop in Visakhapatnam, Andhra Pradesh, he traveled to Sriperumbudur in Tamil Nadu. Upon his arrival at the campaign rally, as he was walking towards the stage to deliver a speech, he was greeted and garlanded by supporters, including Congress workers and school children. The assassin, Kalaivani Rajaratnam, approached Gandhi, and in the guise of bowing to touch his feet, she detonated an explosive-laden belt. The explosion killed Gandhi, the assassin, and 14 others, while grievously injuring 43 additional people.